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Methods for Optimization of Sea Waterway Systems and their Application

safe navigation criteria” (in Polish). A monograph edited by Gucma S. ; Publishing House of Maritime University of Szczecin (Wydawnictwo Naukowe Akademii Morskiej w Szczecinie), ISBN 978-83-89901-82-8. Szczecin 2013. 9. Gucma S., Zalewski P.: “Deterministic-probabilistic method of waterway design parameters determination”. Annual of Navigation, No 19/2012, part 2., ISSN 1640-8632. Gdynia 2012

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Probabilistic Reliability Assessment of Truss Construction in Matlab Software Platform

. [19] LOKAJ, A., K. VAVRUŠOVÁ and E. RYKALOVÁ. Application of laboratory tests results of dowel joints in cement-splinter boards VELOX into the fully probabilistic methods (SBRA method). Applied Mechanics and Materials, vol. 137, pp. 95-99 (5 p). ISSN: 16609336, ISBN: 978-303785291-0, DOI: 10.4028/www.scientific.net/AMM.137.95, 2012. [20] SLOWIK, O. and D. NOVÁK. Algorithmics reliability optimization. In: Proceedings of International Conference Modelling in Mechanics 2014, (12 p). VŠB-TU Ostrava, ISBN 978-80-248-3320-0, 2014. (in Czech

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Reliability Assessment of Existing Structures

Reliability Assessment of Existing Structures

The international standard ISO 13822 provides procedures for the reliability assessment of existing structures including the application of probabilistic methods. Probabilistic approach facilitates to decide about new exploitation of existing structures. Application of probabilistic methods for the reliability assessment of existing structures is shown on the example of deteriorated balcony beams.

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Record Linkage using Probabilistic Methods and Data Mining Techniques

Abstract

Nowadays corporations and organizations acquire large amounts of information daily which is stored in many large databases (DB). These databases mostly are heterogeneous and the data are represented differently. Data in these DB may simply be inaccurate and there is a need to clean these DB. The record linkage process is considered to be part of the data cleaning phase when working with big scale surveys considered as a data mining step. Record linkage is an important process in data integration, which consists in finding duplication records and finding matched records too. This process can be divided in two main steps Exact Record Linkage, which founds all the exact matches between two records and Probabilistic Record Linkage, which matches records that are not exactly equal but have a high probability of being equal. In recent years, the record linkage becomes an important process in data mining task. As the databases are becoming more and more complex, finding matching records is a crucial task. Comparing each possible pair of records in large DB is impossible via manual/automatic procedures. Therefore, special algorithms (blocking methods) have to be used to reduce computational complexity of comparison space among records. The paper will discuss the deterministic and probabilistic methods used for record linkage. Also, different supervised and unsupervised techniques will be discussed. Results of a real world datasets linkage (Albanian Population and Housing Census 2011 and farmers list registered by Food Safety and Veterinary Institute) will be presented.

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Probabilistic Methods for Assessment of Hazard in Transportation Systems

Probabilistic Methods for Assessment of Hazard in Transportation Systems

In this paper there has been presented destruction estimation models of construction elements of aircraft in different cases of the state of readiness. The following cases have been examined:

- when a diagnostic parameter indicating the state of readiness exceeds critical point

- when unexpected failure occurs as a result of overload impulse

- when a diagnostic parameter increases and as a result premature failure occurs

- when damage can be indicated with a diagnostic parameter and an unexpected failure may occur.

Differential calculus of Fokker-Planck type has been used in the model creating.

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A Probabilistic Method for Certification of Analytically Redundant Systems

-angle-of-attack control law development and testing, Journal of Aircraft 38(5): 841-847. Hu, B. and Seiler, P. (2013). A probabilistic method for certification of analytically redundant systems, Proceedings of the 2nd International Conference of Control and Fault-Tolerant Systems, SysTol 2013, Nice, France, pp. 13-18. Isermann, R. (2006). Fault-Diagnosis Systems: An Introduction from Fault Detection to Fault Tolerance, Springer-Verlag, Berlin. Isermann, R. and Ballé, P. (1997). Trends in the application of model-based fault detection and

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A Probabilistic Method of Determining Fatigue Lives of Some Selected Structural Components of an Aircraft to Maintain the Required Flight Safety Level - An Outline

A Probabilistic Method of Determining Fatigue Lives of Some Selected Structural Components of an Aircraft to Maintain the Required Flight Safety Level - An Outline

The paper has been intended to outline a method of determining fatigue life of a structural component of an aircraft for some assumed flight safety level. What has been used in the method in question are as follows:

• Operation-effected spectrum of loading an aircraft's structural component,

• The Paris relationship that determines fatigue-crack propagation rate approached in a deterministic way,

• A difference equation to describe the crack growth by means of a probabilistic approach,

• A density function of crack growth in a structural component in the form of a solution to the Fokker-Planck equation.

The results gained allowed of finding the density function of time (i.e. flying time) indispensable to exceed the permissible crack length. With this function determined, one could determine reliability of the component to be then used to find fatigue life of this structural component. Two solutions have been given consideration, both depending on the m coefficient in the Paris relationship, i.e. for m = 2 and m ≠ 2.

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A Probabilistic Method of Determining Fatigue Lives of Some Selected Structural Components of an Aircraft to Maintain the Required Flight Safety Level - An Outline

A Probabilistic Method of Determining Fatigue Lives of Some Selected Structural Components of an Aircraft to Maintain the Required Flight Safety Level - An Outline

The paper has been intended to outline a method of determining fatigue life of a structural component of an aircraft for some assumed flight safety level. The results gained allowed of finding the density function of time (i.e. flying time) indispensable to exceed the permissible crack length. With this function determined, one could determine reliability of the component to be then used to find fatigue life of this structural component. Two solutions have been given consideration, both depending on the m coefficient in the Paris relationship, i.e. for m = 2 and m ≠ 2.

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The Application of Probability Elements in Optimizing Supply of Spare Parts and Components in Aviation

Abstract

The paper undertakes the problem of managing exploitation support of aviation equipment in terms of spare parts and subassemblies taking into account variable conditions, resulting from different intensity of aircraft and helicopter operation. It covers the practical aspects of planning stocks of material resources in connection with the applicable operating systems and failure of aircraft at the airbase level. By using statistical elements and probabilistic models it indicates the possibility of increasing the availability of parts and aircraft components, which in the long run will make a positive impact on the level of equipment technical efficiency. The article points to the need to minimize the expenditure involved and to avoid redundant, useless aircraft spare parts and components. Therefore, it is aimed at increasing the efficiency of material management, improving safety and developing exploitation systems in terms of technical reliability.

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Landslide Susceptibility Assessment in Constantine Region (NE Algeria) By Means of Statistical Models

Abstract

The purpose of the present study was to compare the prediction performances of three statistical methods, namely, information value (IV), weight of evidence (WoE) and frequency ratio (FR), for landslide susceptibility mapping (LSM) at the east of Constantine region. A detailed landslide inventory of the study area with a total of 81 landslide locations was compiled from aerial photographs, satellite images and field surveys. This landslide inventory was randomly split into a testing dataset (70%) for training the models, and the remaining (30%) was used for validation purpose. Nine landslide-related factors such as slope gradient, slope aspect, elevation, distance to streams, lithology, distance to lineaments, precipitation, Normalized Difference Vegetation Index (NDVI) and stream density were used in the landslide susceptibility analyses. The inventory was adopted to analyse the spatial relationship between these landslide factors and landslide occurrences. Based on IV, WoE and FR approaches, three landslide susceptibility zonation maps were categorized, namely, “very high, high, moderate, low, and very low”. The results were compared and validated by computing area under Road the receiver operating characteristic (ROC) curve (AUC). From the statistics, it is noted that prediction scores of the FR, IV and WoE models are relatively similar with 73.32%, 73.95% and 79.07%, respectively. However, the map, obtained using the WoE technique, was experienced to be more suitable for the study area. Based on the results, the produced LSM can serve as a reference for planning and decision-making regarding the general use of the land.

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